Cytokine interleukin-1β로 誘發된 糖尿病 마우스의 膵臟 glucokinase 및 hexokinase 活性에 對한 五倍子의 效果에 關한 硏究

최형일,정지천,김철호 동국대학교 한의학연구소 1998 東國韓醫學硏究所論文集 Vol.7 No.1

Glucokinase와 hexokinase는 간과 췌장에서 인슐린에 의해 혈당이용을 증대시키며 혈당농도를 감지하여 인슐린 분비를 조절하는 효소로서 인슐린비의존성당뇨병(NIDDM)의 병인과 밀접한 관계가 있는 효소이다. Cytokine의 일종인 interleukin-1β (IL-1β)는 췌장 도세포에서의 인슐린 분비와 β-cell에 대한 세포 독성을 효과적으로 조절하여 장기간 노출시키면 인슐린 분비와 생합성을 저해하며 β-cell을 파괴하여 β-cell의 기능적, 구조적 손상을 초래하여 IDDM을 유발한다. 본 연구에서는 당뇨병 치료의 전통한방약제로서 사용되고 있는 五倍子추출물의 효과를 해명하기 위하여 IL-1β유발 실험적 당뇨마우스의 glucokinase와 hexokinase의 활성을 검토한 결과, lL-1β주사에 의해 체중과 공복시의 glucose 및 insulin 분비가 증가되었으나, 五倍子투여로 공복시의 insulin분비가 감소하였으며 체중과 공복시의 혈당은 유의성은 없었으나 대조군에 비하여 감소하였다. 그러나, 혈당수치가 정상군에 비하여 현저하게 증가되었으나 五倍子투여로 현저히 감소하였으며 Insulin치의 상승과 분비지연도 五倍子투여군에서는 정상군과 유사한 경향을 보였다. 한편, 혈중 glucokinase와 hexokinase의 활성은 IL-1β주사에 의해 현저히 감소되었으나, 五倍子 투여로 유의성 있게 상승되었다. 이상의 결과로, 五倍子는 IL-1β로 유발된 실험적 당뇨병에서 포도당인산화 효소인 glucokinase와 hexokinase의 활성을 증가시키는 것으로 나타났다. We investigated the in vivo effect of an aquous extract from Rhois Galla (R-G) on glucokinase and hexokinase activities of diabetes mellitus induced by interleukin-β (IL-1β). After 1 week of alloxan injection, the levels of serum glucose and insulin secretion were dramatically increased, however, the insulin secretion was decreased with administration of R-G, IL-1β injection allowed the scrum glucose level increased and the level was decreased by R-G administration. Furthermore, we could observe that R-G was effective in recovering the levels of insulin secretion. Enzyme activities of the gtucokinase and hexokinase were decreased by IL-1β treatment. In contrast, R-G administration to the mice allowed proportion increasing. Seemingly, when IL-1β was injected to the mice, enzyme activities of the glucokinase and hexokinase were decreased. But, R-G stimulated induction of enzyme activities of the glucokinase and hexokinase as high as normal group. These results suggested that R-G is highly effective in treatment of diabetes mellitus.

표적세포의 Nitric oxide 합성이 LAK 세포의 세포독성에 대한 예민도에 미치는 영향

박성일,박주형,이치국,김신재,최보금,곽재용,임창열,Park, Sung Il,Park, Ju Hyung,Lee, Chi Kug,Kim, Shin Chae,Choi, Bo Geum,Kwak, Jae Yong,Yim, Chang Yeol 대한면역학회 2001 Immune Network Vol.1 No.2

Background: Nitric oxide (NO), a cytotoxic molecule is produced in various tissues including tumor cells during interleukin-2 (IL-2) therapy . Lymphokine-activated killer (LAK) cells are induced during IL-2 therapy, and have cytotoxic activity against tumor cells. The current study investigated the effects of NO synthesized in target cells or exposure of target cells to NO on the sensitivity of target cells to LAK cell cytotoxicity. Methods: Cytotoxicity was measured using 4 h chromium release assays. LAK cells which were induced by a 4 day incubation of BALB/c mouse splenocytes with IL-2 (6,000 IU/mL) were employed as effector cells. RD-995 skin tumor cells originated from a C3H/HeN mouse were employed as target cells. NO synthesis in target cells was induced by a 24 h incubation of RD-995 cells with $IFN{\gamma}$ (25 U/mL), TNF (50 U/mL) and IL-1 (20 U/mL). S-nitrosyl acetylpenicillamine (SNAP), an NO donor, was used to expose target cells to NO. $N^G$-monomethyl-L-arginine (MLA) and carboxy-PTIO were added during cytotoxicity assays to inhibit NO synthesis, and to scavenge NO produced by target cells, respectively. Results: Sensitivity of NO-producing RD-995 cells to LAK cell cytotoxicity was decreased by addition of MLA and carboxy-PTIO during cytotoxicity assays. However, the two reagents had no effect on the sensitivity of non-NO-producing RD-995 cells. Pretreatment of RD-995 target cells with SNAP increased the sensitivity in comparison with untreated cells. Conclusions: Sensitivity of target cells to LAK cell cytotoxicity is increased by target cell NO synthesis or exposure to NO. Further studies are needed to evaluate whether these in vitro results have relevance to in vivo phenomena.

Effects of the pro-inflammatory milieu on the dedifferentiation of cultured fibroblast-like synoviocytes

CHOI, HONG SEO,RYU, CHUN JEIH,CHOI, HYUN MI,PARK, JIN SUNG,LEE, JAE-HOON,KIM, KANG IL,YANG, HYUNG-IN,YOO, MYUNG CHUL,KIM, KYOUNG SOO D.A. Spandidos 2012 MOLECULAR MEDICINE REPORTS Vol.5 No.4

<P>The aim of this study was to determine whether the inflammatory milieu and/or hypoxia induces the dedifferentiation of synovial cells into mesenchymal stem-like cells, which may contribute to the tumor-like growth of synovial cells. Expression of mesenchymal stem cell markers (CD24, CD44, CD90, CD106, CD146 and Stro-1) was compared among cultured fibroblast-like synoviocytes (FLSs) from patients with rheumatoid arthritis (RA) or osteoarthritis (OA), bone marrow mesenchymal stem cells (BM MSCs) and normal dermal fibroblasts. After the cells were stimulated with pro-inflammatory cytokines for 3 days under hypoxia or normoxia, the stem cell markers were analyzed by FACS. CD44 and CD90 were expressed constitutively in all four cell types. Only the BM MSCs strongly expressed CD146. The expression of stem cell markers was similar between FLSs from RA and those from OA patients. In addition, the expression levels in FLSs were similar to those in normal dermal fibroblasts. The stimulation of FLSs and dermal fibroblasts with IL-1β or a mixture of cytokines under hypoxia did not induce a marked change in the expression of stem cell markers. These results indirectly suggest that the pro-inflammatory milieu may be not sufficient to induce the dedifferentiation of FLSs in arthritic joints.</P>

생쥐의 B 세포에서 anti-CD40과 rIL-4로 유도된 싸이토카인 생산에 대한 자오가의 효과

성일창 ( Il Chang Sung ),김형환 ( Hyung Hwan Kim ),안덕균 ( Duk Kyun Ahn ),이용섭 ( Yong Sup Lee ),서영배 ( Young Bae Seo ),최호영 ( Ho Young Choi ) 대한본초학회 2003 大韓本草學會誌 Vol.18 No.2

N/A Objectives : In order to study the anti-allegy effect of water extract of Acanthopanacis senticosi Radix (ASR) on the B-cells from healthy Balblc mice. Methods : The cytotoxicity of ASR was measured with the murine normal lung fibroblast cells by modified SRB assay. And the murine splenic B-cells was stimulated with anti-CD40 mAb and rIL4. The various cytokines related with allergy were measured by flow-cytometry and by RT-PCR with electophoresis. Results : The anti-allegy effects to ASR were identified and observed. The cytotoxicity of ASR on mouse lung fibroblast cells showed no significant activities. ASR had inhibitory effect on CD23+, CD69+, and IgE expression by ASR with anti-CD40 mAb plus rL-4-stimulated murine splenic B-cells. ASR had inhibitory effect on cytokines (E-lb, IL-4, IL-6, IL-10, TNF-a, TGF-81, INF-Y) and transcript expression and IgE production by ASR with anti-CD40 mAb plus rIL-4-stimulated murine splenic B-cells. Conclusion : We concluded that ASR showed anti-allegy effect on murine splenic B-cells.

Effects of Phenytoin and Diazepam on the Seizure Activity in the Cortical Dysplasia Animal Models

Kim, Si-Hyung,Choi, In-Sun,Cho, Jin-Hwa,Park, Eun-Ju,Jang, Il-Sung,Choi, Byung-Ju,Kim, Hyun-Jung,Kim, Young-Jin,Nam, Soon-Hyeun The Korean Academy of Oral Biology 2006 International Journal of Oral Biology Vol.31 No.2

Dysplasia-associated seizure disorders are markedly resistant to pharmacological intervention. Relatively little research has been conducted studying the effects of antiepileptic drugs(AEDs) on seizure activity in a rat model of dysplasia. We have used rats exposed to methylazoxymethanol acetate(MAM) in utero, an animal model featuring nodular heterotopia, to investigate the effects of AEDs in the dysplastic brain. Pilocarpine was used to induce acute seizure in MAM-exposed and age-matched vehicle-injucted control animals. Field potential recordings were used to monitor amplitude and numbers population spikes, and paired pulse inhibition in response to stimulation of commissural pathway. Two commonly used AEDs were tested: diazepam 5, 2.5mg/kg;phenytoin 40, 60mg/kg. Diazepam(DZP) and phenytoin(PHT) reduced the amplitude of population spike in control and MAM-exposed rats. However, the amplitude of population spike was nearly eliminated in control rats as compared to the MAM-exposed rats. Pharmaco-resistance was tested by measuring seizure latencies in awake rats after pilocarpine administration(320mg/kg, i.p.) with and without pretreatment with AEDs. Pre-treatment with PHT 60 mg prolonged seizure latency in control rats, but not in MAM-exposed animals. The main findings of this study are that acute seizures initiated in MAM-exposed rats are relatively resistant to standard AEDs assessed in vivo. These data suggest that animal model with cortical dysplasia can be used to screen the effects of potential AEDs.

Silibinin polarizes Th1/Th2 immune responses through the inhibition of immunostimulatory function of dendritic cells

Lee, Jun Sik,Kim, Sang Gap,Kim, Hyung Keun,Lee, Tae-Hyung,Jeong, Young-Il,Lee, Chang-Min,Yoon, Man-Soo,Na, Yong Jin,Suh, Dong-Soo,Park, Nam Cheol,Choi, In-hak,Kim, Gi-Young,Choi, Yung Hyun,Chung, Hae Liss 2007 Journal of Cellular Physiology Vol.210 No.2

<P>Silibinin is the primary active compound in silymarin. It has been demonstrated to exert anti-carcinogenic effects and hepato-protective effects. However, the effects of silibinin on the maturation and immunostimulatory activities exhibited by dendritic cells (DCs) remain, for the most part, unknown. In this study, we have attempted to determine whether silibinin can influence surface molecule expression, dextran uptake, cytokine production, capacity to induce T-cell differentiation, and the signaling pathways underlying these phenomena in murine bone marrow-derived DCs. Silibinin was shown to significantly suppress the expression of CD80, CD86, MHC class I, and MHC class II in the DCs, and was also associated with impairments of LPS-induced IL-12 expression in the DCs. Silibinin-treated DCs proved highly efficient with regard to Ag capture via mannose receptor-mediated endocytosis. Silibinin also inhibited the LPS-induced activation of MAPKs and the nuclear translocation of the NF-κB p65 subunit. Additionally, silibinin-treated DCs evidenced an impaired induction of Th1 response, and a normal cell-mediated immune response. These findings provide new insight into the immunopharmacological functions of silibinin, especially with regard to their impact on the DCs. These findings expand our current understanding of the immunopharmacological functions of silibinin, and may prove useful in the development of therapeutic adjuvants for acute and chronic DC-associated diseases. J. Cell. Physiol. 210: 385–397, 2007. © 2006 Wiley-Liss, Inc.</P>

Effect of Cytokines and bFGF on the Osteoclast Differentiation Induced by 1α,25-(OH)<SUB>2</SUB>D<SUB>3</SUB> in Primary Murine Bone Marrow Cultures

Han-Jung Chae,Jang-Sook Kang,Byung-Gwan Bang,Seoung-Bum Cho,Jo-IL Han,Joo-Young Choi,Hyung-Min Kim,Soo-Wan Chae,Hyung Ryong Kim 대한생리학회-대한약리학회 1999 The Korean Journal of Physiology & Pharmacology Vol.3 No.6

<P> Bone is a complex tissue in which resorption and formation continue throughout life. The bone tissue contains various types of cells, of which the bone forming osteoblasts and bone resorbing osteoclasts are mainly responsible for bone remodeling. Periodontal disease represents example of abnormal bone remodeling. Osteoclasts are multinucleated cells present only in bone. It is believed that osteoclast progenitors are hematopoietic origin, and they are recruited from hematopoietic tissues such as bone marrow and circulating blood to bone. Cells present in the osteoclast microenvironment include marrow stromal cells, osteoblasts, macrophages, T-lymphocytes, and marrow cells. These cells produce cytokines that can affect osteoclast formation. In vitro model systems using bone marrow cultures have demonstrated that IL-1β, IL-3, TNF-α, bFGF can stimulate the formation of osteoclasts. In contrast, IL-4 inhibits osteoclast formation. Knowledge of cytokines and bFGF that affect osteoclast formation and their capacity to modulate the bone-resorbing process should provide critical insights into normal calcium homeostasis and disorders of bone turnover such as periodontal disease, osteoporosis and Paget s disease.

Adiponectin is a negative regulator of NK cell cytotoxicity.

Kim, Kun-Yong,Kim, Jae Kwang,Han, Seung Hyun,Lim, Jong-Seok,Kim, Keun Il,Cho, Dae Ho,Lee, Myeong-Sok,Lee, Jeong-Hyung,Yoon, Do-Young,Yoon, Suk Ran,Chung, Jin Woong,Choi, Inpyo,Kim, Eunjoon,Yang, Young American Association of Immunologists 2006 Journal of Immunology Vol.176 No.10

<P>NK cells are a key component of innate immune systems, and their activity is regulated by cytokines and hormones. Adiponectin, which is secreted from white adipose tissues, plays important roles in various diseases, including hypertension, cardiovascular diseases, inflammatory disorders, and cancer. In this study the effect of adiponectin on NK cell activity was investigated. Adiponectin was found to suppress the IL-2-enhanced cytotoxic activity of NK cells without affecting basal NK cell cytotoxicity and to inhibit IL-2-induced NF-kappaB activation via activation of the AMP-activated protein kinase, indicating that it suppresses IL-2-enhanced NK cell cytotoxicity through the AMP-activated protein kinase-mediated inhibition of NF-kappaB activation. IFN-gamma enhances NK cell cytotoxicity by causing an increase in the levels of expression of TRAIL and Fas ligand. The production of IFN-gamma, one of the NF-kappaB target genes in NK cells, was also found to be suppressed by adiponectin, accompanied by the subsequent down-regulation of IFN-gamma-inducible TRAIL and Fas ligand expression. These results clearly demonstrate that adiponectin is a potent negative regulator of IL-2-induced NK cell activation and thus may act as an in vivo regulator of anti-inflammatory functions.</P>

백혈병 마우스 모델의 동종골수이식에서 활성화된 자연살해세포들의 보충이 이식편대백혈병효과와 이식편대숙주반응에 미치는 영향

엄현석,한치화,박수정,김소연,정낙균,정대철,진종률,최일봉,양형모,서영훈,송현근,최인표,민우성,김춘추 대한조혈모세포이식학회 2001 대한조혈모세포이식학회지 Vol.6 No.1

배경: 백혈병에서 동종골수이식 (allogeneic bone marrow transplantation)의 성공적 치료 효과를 얻기 위해서는 이식편대숙주반응 (graft-versus-host disease, GVHD) 발생의 극복과 재발의 방지가 중요한 과제이다. 골수를 역류원심성 세포분리 (counterflow centrifugal elutriation, CCE) 방법으로 분리하여 얻은 rotor off (R/O) 세포분획은 T 세포의 수는 적지만 조혈모세포들을 다량 포함하고 있어 동종골수이식에서 주조직적합복합체 (major histocompatibility complex, MHC) 차이를 극복할 수 있고, 이식편의 생착 성공과 GVHD 발생 예방에 효과적이다. 그러나 골수로부터 T 세포를 제거하면 백혈병세포를 공격하는 이식편대백혈병 (graft-versus-leukemia, GVL) 효과가 감소되기 때문에 백혈병 재발의 빈도가 높다. 자연살해세포 (natural killer cell, NK cell)의 보충 첨가는 동종골수이식 후 GVHD 발생을 줄이면서 충분한 GVL 효과를 얻을 수가 있다. 따라서 저자는 분리 후 IL-2로 활성화시킨 NK 세포들을 골수 R/O 세포분획과 함께 백혈병 마우스 모델에 동종이식함으로써 GVHD와 GVL에 미치는 효과를 관찰하였다. 방법: Balb/c (H-2^(d)) 마우스에서 유래된 A20 (murine B-lymphoma/leukemia cell line, H-2^(d)) 백혈병 세포를 이식 2 일 전에 Balb/c 마우스에 주입하고, 치사량의 전신 방사선을 조사한 직후에 Balb/c 또는 C57BL/6 (H-2^(b)) 마우스의 골수 R/O 세포분획을 꼬리정맥을 통하여 주입하였다. 이들은 모두 이식 후 6-8 주 이내에 사망하였다. 동종이식의 대조군 (n=9)에는 1 × 10^(7)의 R/O 세포분획만을 주입하였고, 실험군 (n=9)에는 C57BL/6 마우스의 비장세포들로부터 단클론항체들을 이용한 negative selection방법으로 분리한 후 IL-2로 활성화된 5 × 10^(5)의 NK 세포분획을 1 × 10^(7)의 R/O 세포분획과 함께 주입하였다. GVL 효과의 판정은 이식 후 14 일과 28 일 째 되는 날 마우스에서 골수, 비장, 간 등을 얻어 백혈병 세포들의 침윤을 조직학적으로 관찰하였으며, GVHD의 정도는 육안적 관찰법으로 평가하였다. 결과: R/O 세포분획만을 이식한 대조군의 골수, 비장, 그리고 간 조직에서는 A20 백혈병 세포의 침윤이 각각 89% (8/9), 78% (7/9)와 22% (2/9)에서 관찰되었고, R/O 세포분획과 NK 세포분획을 함께 이식한 실험군에서는 비장과 간을 제외한 골수에서만 89% (8/9)에서 A20 백혈병 세포의 침윤이 관찰되어 두 군 사이에 장기별 분포의 차이를 볼 수 있었다 (P= 0.0001). 한편 GVHD는 두 군 모두에서 경하게 나타나서 유의한 차이는 없었다. 또한 생착 부전으로 사망한 마우스는 없었다. 결론: CCE를 이용하여 T 세포를 제거한 동종골수이식에서 NK 세포의 보충은 GVHD의 악화는 일으키지 않으면서, 백혈병의 진행을 억제하는 GVL 효과를 얻을 수 있었다. Background: Allogeneic bone marrow transplantation (BMT) with T cell-depleted marrow accompanies engraftment failure and relapse of leukemia by a loss of the graft-versus-leukemia (GVL) effect frequently, while it can prevent GVHD. Supplement of NK cells could prevent GVHD and enhance GVL effect in several murine allogeneis BMT models Roter off (R/O) cell fraction obtained by counterflow centriation elutriatio (CCO) contains small number of T cells and many hematopoietic stem cells. The aim of this study was to determine the effect of R/O cell fraction supplemented with IL-2 activated NK cells on GVL and GVHD within the leukemic mouse BMT model. Methods: Inoculation of A20 (H-2d, murine B-lymphoma/leukemia, Balb/c origin) cells into Balb/c mice via the tail vein 2 days prior to lethal total body irradiation (TBI) and infusion of the Balb/c BM or C57BL/6 (H-2b) R/O fraction were performed. It resulted in 100% mortality within 6 to 8 weeks. The irradiated mice in the control group were injected with 1 × 107 R/O cell fraction alone (n=9) and in the experimental group mice were injected with 1 × 107 R/O cell fraction plus 5 × 105 negatively selected IL-2 activated NK cell fractions of the spleens via the tail vein (n=9). On day 14 and 28 after BMT, the bone marrows, spleens, and livers of mice were harvested for histopathologic analysis of the infiltrations of leukemic cells. We then evaluated the GVHD within the mice. Results: A histopathologic study of the recipients receiving R/O fraction alone showed infiltration of leukemic cells, 89% (8/9) in bone marrows, 78% (7/8) in spleens, and 22% (2/9) in livers. The experimental group of mice showed only the infiltration of leukemic cells 89% (8/9) in bone marrows, not in spleens and livers. There were the organ differences of the leukemic cells infiltrations between the two groups (P=0.0001). There were no obvious differences in the GVHD scores between these two groups, and severe GVHD was not observed. There was no engraftment failure among groups. Conclusion: Thus, our findings suggest that R/O cell fraction obtained by CCE and supplemented with NK cells can promote GVL effect without mediating clinically overt GVHD in allogeneic BMT of mouse leukemia.

하악골 충격시 안면 두개골의 응력분산양상에 미치는 구강보호장치의 역할에 관한 유한요소법적 연구

김일한,노관태,노현식,김지연,우이형,Kung-Rock Kwon,최대균 대한치과보철학회 2012 대한치과보철학회지 Vol.50 No.1

연구 목적: 이 연구의 목적은 하악골 충격 시 안면 두개골의 응력 분산양상에 미치는 구강보호장치의 효과에 대해 조사하는 것이다. 연구 재료 및 방법:: 구강보호장치를 제작하고 사람의 머리부위와 치열의 3차원적 유한요소 모델을 컴퓨터 토모그래피를 사용하여 제작하였다. 머리부위의 finite element model은 356,092요소와, 87,099절점으로 이루어져 있다. 그리고 skull과 maxillae, mandible, articular disc, teeth, 그리고 구강보호장치로 구성되었다. 경부의 움직임을 묘사하기 위하여 스프링이 사용되었다. 하악골의 충격점은 gnathion, center of inferior border 와 anterior edge of gonial angle이었다. 충격방향은 수직, 경사방향(45 도), 그리고 수평이다. 충격량은 0.1초당 800 N이었다. 결과: 수직충격을 가한 경우에는 구강보호장치의 장착여부와 무관하게 비슷한 응력과 분산양상이 나타났다(P>.05). 경사충격(45 도)을 가한 경우 구강보호장치를 장착한 모델에서는 응력이 치아와 안면골 및 두개골로 넓게 분산되었으나 이에 비하여 장착하지 않은 모델에서는 치아에 응력이 집중되었다(P<.05). 수평충격을 가한 경우 구강보호 장치를 장착한 모델에서는 응력이 치아와 안면골 및 두개골로 넓게 분산되었으나 이에 비하여 장착하지 않은 모델에서는 치아에 응력이 집중되었다(P<.05). 구강보호장치를 장착하지 않은 모델에서는 상악 치아에 응력이 집중되는 반면, 장착한 모델에서는 모든 충격실험에서 계측된 응력이 매우 낮았으며, 전달된 응력이 상악 치아와 안면골 및 두개골로 넓게 분산되었다. 결론: 구강보호장치는 외부충격 시에 하악에 수직으로 가해지는 충격에는 완충효과가 적었고, 45 도 경사 충격과 수평 충격에는 발생하는 응력을 안면골과 두개골의 넓은 범위로 분산시키고 응력을 감소시켜 응력의 완충 효과가 있었다. PURPOSE. The purpose of this study was to investigate the effects of a mouthguard on stress distribution under mandibular impact. MATERIALS AND METHODS. The FEM model of head consisted of skull, maxilla, mandible, articular disc, teeth, and mouthguard. The impact locations on mandible were gnathion, the center of inferior border, and the anterior edge of gonial angle. And the impact directions were vertical, oblique (45 degrees), and horizontal. The impact load was 800 N for 0.1 sec. RESULTS. When vertical impact was applied, the similar stress and the distribution pattern was occurred without the relation of the mouthguard use (P>.05). The model with mouthguard was dispersed the stress to the teeth, the facial bone and the skull when the oblique (45 degrees) impacts were happened. However, the stress was centralized on the teeth in the model without mouthguard (P<.05). The model with mouthguard was dispersed the stress to the teeth, the facial bone and the skull when the horizontal impacts was occurred. However, the stress was centralized on the teeth without mouthguard (P<.05). For all impact loads, stress concentrated on maxillary anterior teeth in model without mouthguard, on the contrary, the stress was low in the model with mouthguard and distributed broadly on maxillary anterior teeth, facial bone, and skull. CONCLUSION. The mouthguard was less effective at shock absorbing when vertical impact was added. However, it was approved that mouthguard absorbed the shock regarded to the oblique (45 degrees) and horizontal impact by dispersing the shock to the broader areas and decreasing the stress.